Apparatus for testing sheet material



Oct. 11, 1932. w. B. MEGLITZ 1,881,812

I APPARATUS FOR TESTING SHEET'MATERIAL Filed Aug. 11. 1930 intervals.The qualit ed es of a sample of given size.

,Pgtentedfid. 11,1932

UNIT-an sTATas PATENT orrics wrnnmir nunerrrz, or BERLIN, imwmmrsmnn,assrenon 'ro nnown 0011mm,

1 or BERLIN, new nanrsnman oonronarron oniuanm APPARATUS FOB TESTINGSHEET MATERIAL Application fled Augult 11, 1930. Serial No; 474,390.

This invention relatesto a method of and I apparatusfor-testingthe-resistance of sheet material to bending Y undercompremional stresses applied to the edges-of a sample of given size.-While the invention .is appliit is distributed through the body of thesheet.

with substantial uniformity. Due to various causes, including thetendency of the rubber particles to migrate toward the surface of thesheet as the latex therein is dried, the uniformity of distribution ofrubber throughout the sheet cannot'always be depended upon. In order tomaintain a substantial'uniformity of quality in the product, it isnecessary to make frequent tests from samples taken at of the sheet,which depends largely on t e distribution of its rubber content, can besufiiciently determined in some respects by its resistance to bendingunder compressional stresses applied to the rtificial leather of thetype described is moderately still but is-capable of being bent,

through a considerable angle without fracture. If a sample of given sizeand preferably of rectangular shape is tested by applying compressionalstresses to opposite edges, the sample will bow increasingly as thecompression is increased so that the amount of pressure required toproduce bowing of a sample of standard size may be taken as a measure ofthe quality of the material in the test sample. Instead of or inaddition to measuring the force 're uired to produce a lateral dislacement of t e center of the sample throng a given distance from theplane of the two ends, the distance of approach of the two edges towhich pressure is ap lied may also be observed" as a measure of thequality of the material.

For facilitating the testing of samples of a sheet of artificial leatheror the like I have 1 provided an apparatus by which the amount of forcenecessary to produce a given lateral displacement of the central portionof thesample may be readily measured, also the amount of force requiredto push the opposite edges of a sample toward each other through a givendistance.

Fora more complete understanding of the invention, referencemay be hadto the description thereof which follows and to the drawing, of which,

ing the invention.

Figure 2 is a side elevation of the Sama a Figure 3 is a front elevationof the same.

Figure 4 is a section on the line 4-4 of Figure 3.

The device may include a suitable base or platform from the o posite sids of whlch rise a pair of standar s or rails 1 and 12'. Between thesestandards. a carriage 13 is slidably supported and is guided by thestandards. To this end any suitable guiding elements may be employed. Asshown the 'standards 11 and 12 are grooved as at 14 to receive slidingelements 15 which are a part off the carriage 13. The slides 15 of thecarnage are joined by a cross bar 16 which is grooved as at .17 on itsunder surface, this groove extending substantially from one end of thebar to the other. Directly below the groove 17 and opposed thereto is asimilar groove 18 in the upper face of the platform 10. These groovesareadapted to receive the edges of a sam 1e 20 of sheet material to betested. In or er to ensure the bulging or bending of the test sample inthe correct direction from the plane of its edges, I may. mount a crossrod 21 between the standards 11 and 12 a short distance above the groove18. This cross rod 21 is referably located in a common plane with theooves 17 and 18 so that when the edges 0 a sample are inserted in thegrooves, the mid portion thereof must be out of line with the grooves.

Compressive stresses are applied to the sample under test by firstinserting the sample with its edges in the grooves 17 and 18 and thenplacing weights of increasing magnitude on the carriage 13. These may beplaced on a convenient platform 22 supportv 60 Figure 1 isa plan view ofa device embodyed on the carriage and may be of any convenient form suchas fine lead -shot which can be oured into a-suitable open receptacle 23on t e platform 22 untilthe desired distortion of the sample isattained. As weight is added tothe carri 13 the bendin of the sampleincreases, 7 ere being a' distinct.

bendor bul e corresponding to the weight ap lied to e carriage.

usin the device, the sample is inserted therein with its upper and-loweredges in the ves 17 and 18. As theweight ion the carnage 13 isincreased, the distortion; of the sample is constantly observed,f,thisdistortion including the amount of lateral bulge of the mid portion ofthe sheet fromygt-he' plane of the upper and lower edges of the-isample,and

' the movement-of the opposite-edges ofthe sheet toward each otherunder-the res'sllre of the weight on the carriage 13.: order todetermine the amount of bul e may'provide an upright feeler '30 whic byaslide 31 fittedina dovetail g oove 32 in the lpper face of the platform13. A'suitable iil v move'fov'er a scale 34 mounted-*on the upperfac'e'of the latform and thus-"to indicate the amount oful finger piece35' may be flnibuntedf fon t e slide131" to-Zfacilitate the ma ipulationthereof. when jit is, desired to "pushtheffeeler inwardl a ainst' thesurface offa sampleto be teste I he'scale member preferably formed of-afslide which slidesinfaldovetail groove36 in the upper ace- ,o;.theplatform [A set screw 37 is -"provided' to hold the scale member 34adllstabl in (place. This scale member can rea y a 'justed for,testingsheets of different thickness by loosening the set screw 37 to permitadjusting movement of the member 34.

The distance of the movement of-the edges of the sample towardeach othermay be indicated by an index 40 mounted on a convenient portion of thecarriage 13 and adapted to coo rate with anumber of scale divisions 41which may be upon one of the standards 11 or 12. A set screw with aknurled head for convenient manipulation may be thread- -ed through thestandard 12 so as to bring its-inner end into binding contact with one iof the slides of the carriage. Thus a position shown in Fi f use ofhothands'to arrange the .sli ht turn ofthe screw 42 with the fingers orarily holds the carriage in the elevated re 3. This permits sample inos'ition for When the carnage is owned so that its-groove 17 receivesthe u 'per edge of the sample, the feeler may then be moved forwardlyinto contact with the bulgin faceof the sample.

*Then increasing weight is applied to the carriage platform 22 until theeeler is pushed outwardly to a given point on the M2134,

or until the index 4 0 1n its descent re hes ex 33 is "mounted onithe1slide"31 to a desired division of the scale 41. j When either orboth index members have reached addition of weight to the'platform, 22ceases and the accumulated weight thereon isdetermined; The amount ofweight required to produce a given distortion of a sample depends uponthe nature of the sample, that,

is the distribution of rubber through the body ofghe shfiet. freq h 3 yma ing uent tests wit applicant s device, the uality of the artificialleather roduct can maintained substantiallyuniorm since achange in thequality of the. product is at once reflected in its resistance.- to bendagainst the application of compressional stresses.

I claim: .1. A device of the class described comprising a platform, apair of vertical rails rising therefrom, a carriage slidablezup and downbetween said rails, said platform and carriage having a pair of opposinggrooves, one over the other, to receive opposite edges of a piece ofsheet material to be tested, and an upstandingfeeler horizontallyslidable on said platform toward and from the plane of said grooves. f

the desired point on the scale, the further a 2. A: device of the classdescribed 'com prising a platform having a groove therein to receive anedge of a piece of sheet material to be tested, a 'carfiiage having anop' osparallel to the. rst

orm having an opposing work-receiving.

groove above and parallel to tliegroove in the platform, means forguiding said carriage for vertical movement toward and from saidplatform, a fixed horizontal bar between and parallelto said ooves,,.a'nupstanding feeler slidable in said platform "toward and from said bar,and means for indicating the horizontal distance of said feeler fromsaid bar. 1 i

. In testimony whereofI have afiixed' my signature.

